During the last 100 years the electricity distribution systems evolved by acquiring a stable and safe configuration, providing reliable and low cost energy to support the development of nations around the world. Technologically, however, the power systems have not kept major improvements as occurred in the fields of electronics, telecommunications and computing, carrying essentially the same ideas, forms and the same original problems.
Despite the large capillarity, because the distribution network has to reach every individual residence, the information collected and stored by utilities are relatively sparse. This is mainly due to the lack of low cost and reliable communication from the many end branches of the system.
As an example of the difficulties imposed by the lack of information on the current distribution system, in case of a power outage at a client, the energy distribution company, in almost all cases, has no way to detect the fault unless the client reports the failure, even if the fault is in the distribution network itself. Almost all information available consists of monthly consumption readings performed by a human meter reader, made locally on each client.
Also, in cases of power cut-off for nonpayment and reconnection after payment settlement, the company has to move a vehicle to the client installation to perform these functions. Considering that distribution companies have thousands and even millions of clients, this implies that the costs involved in these operations are quite high.
The need for modernization of power systems has generated global initiatives such as the “Smart Grid”, encouraged by DOE—United States Department of Energy, where the emphasis goes through modernization and new technologies mainly by integrating a communication network with the power system. Although there are several technologies available, the biggest problem for its implementation is the huge investment involved, which would only be amortized over several years.
Apart from modernization initiatives, a chronic problem of distribution networks is related to energy losses, which are classified in technical losses and commercial losses.
Technical losses are related to the energy transport in electrical cables and equipment for imposing a resistance to current flow and are therefore related to the laws of electromagnetism, or more specifically, the Joule's law.
Commercial losses are related to the process of commercialization of energy and involve errors in measurement and consumption reading, errors in the billing process and especially frauds and energy thefts. Fraud refers to tampering with energy meters with the goal of reducing the consumption recorded. Thefts are characterized by illegal connections that divert the energy so that it is not registered by the meter.
Commercial losses not only represent lost revenue for utilities, but also a huge loss to society because there is no related tax collection and part of the prejudice is transferred to the energy rate of regular customers, burdening businesses and the population.
According to estimates made by Brazilian National Electric Energy Agency (ANEEL), commercial losses are responsible for about 15% of the total active power purchased by distribution companies, representing a huge loss to society.
This patent intends to make economically viable several important functions for the process of power distribution through a substantial reduction of losses caused by fraud and energy theft. So below, emphasis will be given to this problem.
The most common types of fraud include a wide range of tampering with consumption measurement, such as waging the meter disk via external agent, breaking the meter seal for tamper with the mechanism or electro-electronic part and various other methods often very creative, making their detection difficult by the energy distributor.
Popularly called “cats” (Translator note: slang used in Brazil), energy thefts are usually direct wire-connection on secondary network or on the service drop (cables connecting the utility pole to the box where the energy meter is installed) without any measurement.
The vast majority of patents aimed at reducing commercial losses targets the two main points affected: the power meter and the secondary network, including the service drop, but it is easy to conclude that it would be necessary to use several techniques associated to have effective protection against fraud and energy theft. In fact, the energy distribution companies develop a series of actions aimed at reducing these unlawful practices of electricity subtraction and, despite all efforts, it is clear that the solutions currently in use have proved to be ineffective and, to minimize the possibility of fraud and energy theft by the end users, the techniques and equipment need to be improved.
Analyzing the various documents existing on the subject, the difficulty is perceived.
The following utility models and patents refer to attempts to hinder fraud on energy meter, either by using better meter technology or by making tamperproof boxes that contain the meter:                MU8802110-6—Disposicao em Medidor Eletronico de Energia Eletrica com Tampa Lacrada (Provision at Electrical Energy Metering with Cover Sealed);        MU8402469-0—Disposicao Construtiva Aplicada a Caixa de Medidor de Energia Eletrica com Sistema de Lacre Inviolavel (Constructive Disposal Applied to the Box of Electric Power Meter with System of Inviolable Sealing);        PI0719731-4—Medidor de Energia Eletrica, Compreendendo pelo Menos Um Captador de Medida de Corrente de Tipo Indutiva e Captador Associado (Electric Energy Meter, Comprising at Least One Collector of Current Measure of Inductive Type and Associate Collector);        PI0703743-0—Gabinete de Medidor de Energia Eletrica (Electric Energy Meter case);        PI0104930-5—Medidor de Energia Eletrica Contra-Ativo as Fraudes (Electric Energy Meter Counter-active to fraud);        PI0002109-1—Sistema e Metodo de Deteccao de Adulteracoes/Anomalias em Medidores de Energia Eletrica e Medidor que Utiliza este Sistema (System and Method for Adulterations/Anomalies Detection in Electric Energy Meters and Meter that Uses this System).        
None of these solutions, however, prevents the deviation that is made directly from the distribution network, featuring the power theft.
In particular, the document U.S. Pat. No. 5,940,009—“Apparatus and method to detect tampering with an electronic utility” combines, in the same device, a unit of measurement and a remotely controlled breaker. The detection of electricity fraud or theft is based on measuring the voltage on the load side, just after the breaker and also within the meter. This procedure is not effective because the client installation can be easily changed by placing an insulation device, as a contactor, after the meter and before the client load, which makes the developed voltage measurement technique innocuous.
The document PI0202535-3—“Cabo Conc ntrico Baixa Tensao para Circuitos de Distribuicao de Energia Eletrica” (Low Voltage Concentric Cable to Electric Power Distribution Circuits) addresses the problem of making connections directly to the network by using the cable conductors arranged concentrically. If one tries to drill the cable access phases, a short circuit would be caused. However, the use of this cable is restricted to client's service drop, between the utility pole and the client measurement box, due to the cost of the cable and its limited current capacity. Thus, even though its use efficacy in service drops, the problems of direct connection to the secondary network and tampering measurement still remain.
The documents PI0701530-5 (“Metodo e Aparato para Indicar a Ocorr ncia de Furto de Energia Eletrica em Redes Eletricas”—Method and Apparatus to Indicate the Occurence of Electric Energy Theft in Electric Grids) and PI0505261-0 (“Aparato para Inibir o Desvio em Circuitos/Redes de Energia Eletrica”—Apparatus for Inhibit the Bypass in Circuits/Grids of Electricity) follow similar approaches among them, superimposing a DC (direct current) voltage on the circuit. The superimposed voltage is removed by a filter so that the energy can be supplied within legal parameters and thus consumed without restriction. In the first document, the signal is only used to indicate the energy illicit use and in the second case the intention is to make energy unfit for consumption if the filter is not used. These approaches have two major problems. The first relates to the easy way of getting a similar filter for DC signal elimination, thus making energy available. A filter that is not authorized by the company could be easily assembled or stolen from another client installation. The second problem, in the case of making energy unfit for consumption, is that purely resistive devices such as showers, would be unaffected by the superimposed DC voltage, functioning satisfactorily.
The document PI0505840-6—“SAFE—Sistema Anti-Furto de Energia Eletrica” (ASEE—Anti-theft System of Electric Energy) aims to eliminate power theft through two simultaneous current measurements, one before the conventional client meter and the other located on the utility pole. The difference in the measured currents indicates an energy diversion that is signaled by a light emitting diode (LED) on the instrument housing. This device detects the energy theft on the service drop, in other words, between the pole and the meter, but does not detect secondary network energy theft or metering fraud.
The document PI0701290-0—“Sistema de Medicao Centralizada de Energia Eletrica” (Centralised Measurement System of Electric Energy), uses an approach of centralizing all meters in a single box, along with a command center, sealed and installed in the distribution network or in closets. The technique described in this document does not detect energy theft made directly from the cables of the secondary network, since only the service drops and power meters are protected. In addition, customers with higher loads may claim that the electrical losses in service drop, being responsibility of the power company, were being charged directly from him (client) since the measurement occurs before the service drop, which will certainly bring legal and billing settlement issues for utility companies.
The document PI9902611-2—“Processo de Identificacao dos Consumidores Fraudadores em Uma Rede de Distribuicao de Energia Eletrica, Numa Determinada Regiao, e Sistema e Processo de Determinacao da Exist ncia de Condutores Escondidos, Que Nao Passam Por Um Medidor de Energia Eletrica” (Identification Process of Fraudsters Consumers in Electric Energy Distribution Grid, in a Determined Region, and System and Process of Determination the Existence of Hidden Conductor, that do not Pass Through a Electricity Meter), intends to identify the energy fraud or theft through a repetitive procedure of group measuring, followed by shutdown of each individual client and their reconnection, done remotely. After shutdown/restart of all clients, the measured values are analyzed to detect possible deviations. This approach is only feasible for a very small number of customers and presents several problems, such as:                Theft or fraud would be detected only if there is consumption at the time of measurement;        For a real number of customers in a distribution company (thousands/millions) the procedure would be unfeasible because it would require a very long time to test all clients;        The distribution company would have their service continuity index worsened, which could result in penalties imposed by the Agência Nacional de Energia Elétrica—ANEEL (National Agency of Electric Energy—NAEE).        
The patent documents U.S. Pat. No. 7,539,581—“System and method for on-line monitoring and billing of power” and U.S. Pat. No. 7,271,735—“System for the remote data acquisition and control of electric energy” as well as the document WO2007139842—“Automated meter reading system, communication and control network for automated meter reading, meter data collector, and associated methods” propose architectures exclusively for remote energy consumption reading and are not directed to the functionality of detecting fraud or energy theft. Similar methods are used for communication between the meters, intermediate units and central processing unit, however, the measurements are not made in order to obtain a phasor sum to detect abnormalities in the circuit, mainly because of the intermediate units do not have any capability of measuring or checking electrical parameters. Furthermore, they do not address the need for safe procedures for network setup operations such as installation, substitution and removal of devices. It is relevant to note that, in case of communication failure, these systems do not provide alternative mode of operation.
The article “Proposta de Sistema de Arquitetura para a Implementacao de uma Smart Grid na Rede de distribuicao em Baixa Tensao”—(Proposed Architecture System for the implementation of a Smart Grid at the Low Voltage Distribution Grid)—(R. C. Gomes, A. L. Printes, C. M. Ramos—III SBSE, Bethlehem Pa., 18-21 May 2010) describes a relatively similar architecture, but uses “Distribution Units (UD)” installed on utility poles to make consumer measurements in a centralized manner, while the present invention dispenses this equipment, allowing to keep the clients' measuring units on their own consuming facility, as currently occurs in almost all low voltage distribution networks, reducing significantly modification and installation costs. This article employs the energy balance technique to attempt to detect fraud and energy theft. This technique is common to other measurement systems available in the market and consists of measuring the active or total energy in a central point, called in this article “Telesupervision Unit (UT)” (corresponding to the Command Central of the present invention) and comparing the measured value with the sum of all measurements in the low voltage circuit. Since energy is the sum (integral) over time of the powers observed, this technique requires an accumulation time, typically a few days or weeks, due to the required resolution, to be able to compare the energy measurements. Despite of this necessary time, observed in all real implementations of this technique, the article claims to allow “the detection, location and quantification of losses, almost instantly,” what does not appear feasible in practice. Furthermore, this technique is not suitable to detect differences caused by the public lighting loads, present in almost all low voltage urban circuits, and neither the energy losses in the circuit, making the detection coarse and inaccurate, allowing to detect only the cases where there is massive fraud or theft. Another important aspect is that there is no security procedure to avoid the replacement of irregular meters adulterated in UD's, making the energies sum being consistent with the measurement at UT (except losses and street lights, as quoted), making frauds undetectable.
The U.S. Pat. No. 6,014,089 “Method for transmitting data using a digital control channel of a wireless network”, with filling date Aug. 26, 1997 and granted in Jan. 11, 2000, and the article “Configuring and Managing the Large-Scale Monitoring Network: Solving Real World Challenges for Ultra-Low Powered and Long-Range Wireless Mesh Networks” (C. Dugas—International Journal of Network Management, 2005, 15: 269-282) use a device that looks like the Operative Interface Module which acts as a multifunction portable collector to collect, download, upload and adjust data and parameters of the secondary circuit, as many other systems currently available in the market, however it does not have the fundamental function used here, which is to reinforce and ensure the safety of the measuring system in the operations of installation, removal and replacement of Metering Modules or Command Central. The proposed security function for the Operative Interface Module makes the measurement system significantly more robust and less prone to energy fraud and theft.
The U.S. Pat. No. 5,995,911 “Digital sensor apparatus and system for protection, control, and management of electricity distribution systems”, with filling date Feb. 12, 1997 and granted in Nov. 30, 1999, has a sensor and system mainly focused on protection and control of three-phase internal distribution networks. Despite of using the name “power distribution systems”, the patent refers to internal networks, within private distribution installations, typically industrial, and not the public networks of power distribution companies or utilities. The system described presents several problems related to mitigating fraud losses and energy theft when related to distribution companies' networks, because:                Does not contemplate or include public lighting charges;        Allows installation of tampered sensors or even new illegal sensors without control over them because there is no security procedures for installation, removal and replacement of sensors;        It is applicable only to internal networks and three-phase loads of consumers (typically industrials), while the distribution networks can be mono-, bi- and three-phasic and come with one, two or three phases loads;        Uses synchronizing technique by GPS (Global Positioning System) in each sensor to establish the necessary phasor measurements, making the total system cost very high to be feasible to the typical distribution networks;        Allows measurement of part or subset of the monitored circuit that precludes the detection of fraud and theft on the network, because there is no way to directly compare the measured values of the subset of sensors with the centralized measurement, which covers all the circuits.        